Snap-switch.



M. GUE-TT.

SNAP SWITCH.

APPLICATION FILED 0m21.191s.

1,294,012. Patented Nov. 7, 1916. @i091 i C; 1f 6i@ 2.

jj Z\ nd I MCNROE GUETT,0F HARTFORD, CONNECTCUT, ASSIGNOR TO HART sI-IEGEMAN MANUFACTURING COMPANY, OF HARTFRD, CONNECTICUT, A CORPOEATON0F CONNECTICUT.

SNAP-SWETCH.

To ZZ whom t may concern.'

Re it known that l, Moisson GUETT, a ritizen of the United States,residing in Hartford, in the county of Hartford and State ofConnecticut, have invented the follrnving-described new and usefulImprovements in Snap-Switches.

This invention relates to electric snap switches designed for productionat a minuimum cost for material and' assemblage, and to such end itsobject is to utilize sheet material substantially throughout the wholeof the snap-mechanism and in such form as to be Capable of expeditiousmanufacture in automatic stamping or pressing machinery, and of rapidassembly, and with the fewest possible number of parts consistent witheconomy of material. V

The invention comprehends various mechanical embodiments of theprinciples of production, construction and assemblage hereinafter fullyexplainedv and as pointed -out in the claims appended hereto.

In the drawings: Figure l is a plan view of a double-pole switchembodying my invention; Fig. 2 is a longitudinall section of Fig. l withparts'broken out; Fig. 3 is a central section through the switch parts,showing the contactblade open; Fig. t is the same view, closed; Fig. 5is a perspective assembly of the base and rocking spring carrier; Fig. Ga cross-section illustrating the journals of the three main parts; Fig.7 is a detail of the crank shaft; Figs. 8 to 10 are details lateridentified; and Fig. l1 is a modified detail. y

As common in the class of rocking spindle switches, the operated memberof the present switch is a contact blade 1, which snaps into alternatepositions, in one of which it bridges two opposite contact terminals 2,and in the other of which it is separated fromv both terminals tointerrupt the circuit at two points. The blade is carried by, butinsulated from, the rocking spindle, herein termed the crank shaft, andthe latter is actuated by two push buttons,.or equivalent means, thesnap actionbeing produced by the connecting parts which include aspring. lln the particular switch taken for illustration there are twocontact blades,` one at each end of the crank shaft, and two pairs ofcontact terminals, constituting a double-pole switch, but it will beapparent that the number of poles is optional with the manufac-Specificaton of Letters Patent.

Patented Nov. 7,' ftil.

Application led December 27, 195. Serial No. 68,916.

turer and quite independent of the principles of constructionconstituting this invention.

The actuating mechanism whereby the push member or members controls theblade, is comprised of but three main parts, each a simple sheet metalstamping, as follows,- a base or bracket 3, a lspindle or crank-shaft el(bearing the contact blades) and apushoperated rocker 5 6. The sheetmetal bracket 3 is formed with a pair of opposite bracket-arms 3a,punched to form two alined crankshaft bearings 3b (Fig. 9) which areprovided with access slots 3 to admit the journal portions la (Fig. 7)of the crank shaft t. The latter, being a flat, sheet-metal stamping, asshown in Fig. 7, is introduced laterally through these slotsand so as toengage by its edges, the edges of the hookshaped portions constitutingthe bearings 3b, in which relation the crank-shaft is retained by itscorrelation to the other parts. One or both ends of the crank shaft isstamped with a two-armed enlargement or head el", forming its attachmentwith the blade or blades, the latter being slotted toV fit the armswithout contact and sandwiched thereon between insulating washers 7 andmetal washers 8, which are all clamped firmly and permanently againstthe base of the head, by upsetting or riveting the ends of the armsagainst the outermost washer, as shown in Fig. 6. Obviously, a singlearm head or other means of attaching the blade to the arm, withoutelectrical connection, can be employed with similar effect, but thedoublearm head is preferred on account of its obvious security andbecause the enlargement represented by the head forms a suitableshoulder for engagement with the outside of the bracket arm to preventendwise displacement of the crank shaft and thereby insures correctalinement of the blade with its contact terminals 2, notwithstanding eX-Acessive wear.

It will be noted that the crank-shaft and its blade-attaching arms orrivets, as well as its shoulder portions, are all in one piece,simultaneously produced in the stamping machine. The crank portion 4* ofthe crankshaft is disposed between the arms of the bracket and receivesits throw from a stout helical spring 9 connected thereto in anysuitable manner, as, for instance, by hooking the end of the springthrough a hole punched in the center of said crank portion. The otherend of this spring is connected to theJ push-operated rocker orspring-carrier and isl adapted to be carried byl it across the plane ofthe crank shaft and far enough beyoud to cause the crank to throw. Thisrocker is likewise formed of a sheet metal stamping and in the presentcase is made of two symmetrical duplicate parts 5 `and 6, placedtogether as indicatedinFig. 5, and fulcrumed on two studs 10, one oneach arm 3 of the base 1. The location of said stud fulcrums is centralwith respect to the throw of the crank shaft and between the base-of themechanism and the crank shaft bearings. Such location, however, issubject to variation, as will become apparent from the furtherdescription of the device, andthe fulcrum axis might be coincidentwiththe crank axis if desired, but it is desirable that the upper end of thespring be moved through as wide anangle as pomible and for that reasonthe fulcrum is preferably as near to the base of the bracket as isindicated in the drawings. The fulcrum stud 10 is produced on each ofthe arms 4 at the time the base 1 is blanked out of the sheet metalstock, and by extrusion of the metal, so that it is therefore integralwith the bracket. This is done by a suitable plunger, forming part ofthe die mechanism, and which by making the indentation 10u (Fig. 9) onone side of the blank forces a' corresponding amount of metal into a diecavity of smaller diameter on the other side. The two halves or parts ofthe spring-carrier are punched with holes conforming to `theirrespective studs and are placed thereon with their inturned arms 5a and6 brought together so as to form a single hook or hole 11 for connectionwith the actuated end of the spring v9, and the latter when attached tothe said hook serves to hold the two parts of the carrier together andalso in alinement with each other, so that they form in effect a unitarystructure. The arms of the carrier member which project from each sideof its ful'cr-um, are provided with eyes 12, and the stamped sheet metalShanks of the pushbuttons are formedwith .outstanding lugs 13 to engagetherewith. These lugs also assist in retaining theL parts of the carriertogether and upon their respective studs, as may also the crank portionof the crank shaft which occupies substantially the full width of thespace between the side plates of the`rocker. By one or all of theseagenvcies the two-part spring-carrying rocker member is retained inoperating relation, in which it may rock in either direction, under theforce of one of the buttons, until it encounters and is stopped by theedge of the bracket base on one side or the other.

The spring 9, being normally undertension, exerts its force on the crankshaft to hold itat all times firmly upon its hook bearings 3b, on whichit may either be caused to slide or rock as desired and according to theshape of the bearings. When'the rocker carries the upper end of thespring across the plane of the crank, the latter is thrown from oneposition to the other, either opening or closing the switch, and theextent of its throw is limited, in both directions, by stops, which, inthe preferred structure, are formed by the corners of the bracket base,bent up to form a pair of lugs 14 on each side, and which'take theimpact of the crank upon their edges. An alternative means of limitingthe crankshaft throw is shown in Fig. 11,.wherein the two screws 15which screw the bracket to the bottom ofthe insulating receptacle, 16,are made long enough for their projecting ends to serve as stops, Thelug-form stops as first describechare preferred because they may be madeautomatically in the press and of the same material as the bracket, andhence with greater economy, the process of assembling being also simpleandquick. Such process may be performed by first placin the two parts ofthe carrier on the lug 13 o the button Shanks and then on their fulcrumstuds 10, which can be done by slightly skewing the said parts whenintroducing them into the bracket and without straining them or the fbracket; the crank shaft is then placed between the stop lugs and in itshook bearings 3", and the spring is then attached to itand to the hook11 of the rocker, which locks all of the parts against any possibilityof displacement. By the aid of suitable temporai-y holdingappliances,`these successive operations can be performed with greatrapidity, and inasmuch as each part of the switch is a simple stampingand can' be rapidly and automatically produced from sheet stock, it willbe evident that the cost of production of the switch is low while theresulting structure is manifestly strong and durable.

The bracket equipped with rocker, crankshaft spring and buttons, issecured to the bottom `wall of the receptacle 1,6, and the buttonsintroduced into the holes'in the plate 17, which guides them and inwhich they 'have a substantially rectilinear movement, due to the shortarc through which the arms of the rocker-are required to move. Thecontact blade is thereby brought into alinement with the terminals 2which are securedV to the rim part of the receptacle by screws 19inserted from the bottom in the usual way. rlhe arms of the contactblade are formed at an angle to each uother or in the shape of an obtuseV, so that a line joining their two extremities is considerably removedfrom the axis of the crank-shaft, and by virtue of this shape both armsextend away from the bottom of the receptacle Lace-,oie

when in the circuit closing position, as shown in Fig. 2, therebyeliminating the necessity of locating one of the contact ter.

this shape of blade, the said terminals mayl both be formed of similarsimple stampings, as indicated in Fig.; 8, and with their contactportions closely adjacent to their binding screws 20 for the wireconnections, so that they are both thus composed of a minimum amount ofmetal, brass, and hence produced at the least cost.

lt will be evident that the basebracket 3 may be made of variousconfigurations to accomplish the purposes above described, and providethe open or hook bearings forV the crank shaft and that the latter issimilarly subject to variation from the particular contour indicated,while still preserving its interlocking relation to its bearings and thebase, as above described, and eliminating special elements or specialacts in its construct-ion. The said shaft as shown canl be completed ina single-stroke of the stamping machine or press, ready to receivethecontact members and their insulation. n the case of the single poleswitch, one: of the heads l can be reduced to'such shape and size aswill still constitute a yshoulder on the shaft for the purpose above described, or it may be eliminated entirely, or left as shown in Fig.7,-without a contact blade. .lit will be evident without explanationthat the rocker member 5-6 could, if desired, be made of a single piecesheet metal stamping, joined at the hook-1l, or elsewhere, but bydividing it into two parts, the sheet metal. stock can'be utilized withless scrap andthe result of a single piece can be secured by the lockingeiect of the spring and other parts as described.

lt is thus apparent that the invention is in no wise limited to theparticular conformation of the principal parts but may comprehend othersheet metal forms having the same principles of structure andassemblage, and therefore l ,particularly claim said invention asfollows:

. l claim.: 4

1. ln a snap switch, the combination of a stamped sheet metal brackethaving hook bearings formed therein, a crank shaft-introduced laterallyinto said bearings, a tensioned spring connected by one end to saidcrankshaft, and actuating means connected to the other end of'l saidspring and adapted to carry the same across the plane of said crankshaft in either direction.

2., ln a snap switch, a bracket member, a crank shaft member journaledtherein, -a rnckermember fulcrumed on' the base, each of said 'membersbeing formed of sheet metal stampings, in combination with a springsecured by one end to the crank shaft and by the other end to saidrocker member and adapted to be carried thereby across the plane of thecrank shaft.

3. In a snap switch, a bracket provided with bearings, ailat crank shaftmember formed of stamped sheet .metal engaging said bearings by itsedge, means including a spring for imparting a snap movement to saidcrank shaft upon its said bearings, and acontact blade carried by thecrank shaft.

4. n a snap switch,-the combination with a bracket having open bearingstherein, of

a crank shaft engaging said bearings and integral shoulders o nsaidcrank shaft for preventing endwise displacement thereof.

5. In a snap switch, the combination with a bracket member' and a crankshaft fulcrumcd thereon, of a two-part rocker member also fulcruniedthereon, and a springl connecting said shaft to the rocker andserving-to lock the parts of the latter in their normal position.

6. In a snap switch, the combination of a sheet metal bracket havingbearings therein provided with access slots', a sheet metal crankshaftjournaled in said bearings and introduced therein through said slots, aspring connected by one end to said crank shaft, and means for carryingthe other end of said spring across the plane of said crank shaft ineither direction.

7. ln a snap switch, abracket providedwith bearings having access slots,a4 dat cra-nk shaft member formed of stamped sheet metal engaging saidbearings by its edge and introduced laterally therein through saidslots, and means including a spring for imparting a snap movement tosaid crank shaft upon its said bearings.

8. In a snap switch, a base or bracket having arms provided with hookbearings, a stamped, flat, sheet-metal crank-shaft introduced laterallyinto said bearings, and integral shoulders on said crank shaft forengaging said bracket arms to prevent endwise displacement of saidshaft, in combination with a spring to operate said crank shaft vineither direction.

9. ln a snap switch, the combination o f a base provided with bracket4arms having bearings with access slots and having lntegral fulcrumstuds on their inner faces, a rocker having arms pivotally supported onsaid studs, a sheet met-al crank shaft introduced into said'bearingsthrough said slots, contacts carried by said crank shaft, and a tensionspring connecting said crank shaft and said rocker for ,holding saidcrank shaft and said rocker in extreme positions.

10. 'in a snap switch, the combination of a base provided withbracketarms having bearings with access 'sietey and having integral fulcrumstuds on their inner faces, a. rocker fulcruined on said studs, a shoul-10 a receptacle 'having short contact terminals secured at oppositepoints near the rim thereof, a rotary shaft member mounted within thereceptacle and carrying a V- shaped Contact b1 ade adapted to bridgesaid terminals, :L spring to actu'ate said shaft 15 member andbutton-means to actuate the spring.

In testimony whereof, I have signed this specification.

MONROE GUETT.

